Canine Cancer: Lymphoma
Learn about the symptoms, diagnosis and treatment of this common canine cancer.
Diana Laverdure |
Posted: August 12, 2014, 4 p.m. PST
Lymphoma is a common form of cancer that originates in the lymphatic system, a network of vessels, nodes, and organs that are part of the circulatory system.
"The lymphatic system produces B-lymphocytes and T-lymphocytes, disease-fighting white blood cells that travel through the blood in a fluid called lymph,” says Mona Rosenberg, D.V.M., a board-certified veterinary oncologist and founder of Veterinary Cancer Group, which has four locations in Southern California. "Lymphoma occurs when lymphocytes grow uncontrollably, forming tumors in the lymph nodes that can spread to the organs, tissues, and bone marrow.”
Symptoms of Dog Lymphoma
The most common sign of early-stage lymphoma is enlargement of one or more lymph nodes, located near the front of the jaw, in the armpits and groin, at the front of the shoulders, and behind the knees. "Many owners discover the enlarged nodes when petting their dogs,” Rosenberg says.
More advanced signs include:
- Anorexia, or lack of appetite
- Excessive drinking
Risk Factors for Dogs with Lymphoma
Although any dog can get lymphoma, certain breeds are genetically predisposed, including:
Lymphoma occurs equally in males and females, with middle-aged to older dogs most often affected.
- Cocker Spaniels
- Retrievers, including Golden and Labrador Retrievers
- St. Bernards
Diagnosis of Lymphoma in Dogs
The first step of diagnosis is typically a fine needle aspiration, during which the veterinarian inserts a tiny needle into an enlarged lymph node to extract a cell sample. The cells are viewed under a microscope to determine if they are abnormal.
Other tests include:
Lymphoma is classified by stage — ranging from 1 to 5 — and the type of lymphocytes affected. "Dogs at all stages can respond to treatment and go into remission,” Rosenberg says. "However, dogs with B-cell lymphoma statistically live longer than those with T-cell lymphoma.” About 75 percent of canine lymphomas are B-cell.
- Core needle biopsy to check for tissue abnormalities
- Blood work to look for cancer in the organs
- X-rays to check for cancer in the lungs
- Ultrasound to look for cancer in the gastrointestinal tract and surrounding organs
Treatment for Dogs with Lymphoma
Since lymphoma travels in the bloodstream, veterinarians use chemotherapy drugs to target the entire body. Rosenberg says that a typical protocol involves a combination of pills and injections administered over a six-month period.
"Ninety percent of dogs treated with chemotherapy go into remission, and most don’t suffer any adverse side effects,” she says. Untreated dogs typically live only four to eight weeks from the time of diagnosis, while the median survival time for treated dogs is about one year.
Rosenberg advises that owners discuss treatment options with their veterinarian and a veterinary oncologist to determine the appropriate protocol.
Although no known prevention for cancer exists, Rosenberg recommends a healthy lifestyle that includes adequate exercise, a nutritious diet, and avoidance of unnecessary environmental toxins.
More on Canine Cancer
Give us your opinion on Canine Cancer: Lymphoma
Login to get points for commenting or write your comment below
Get New Captcha